A152058 Primes in A152057 in the order of their appearance.

3, 7, 31, 127, 8191, 173, 131071, 524287, 2147483647, 699053, 3313, 13271393, 2305843009213693951, 209659, 9361975431089, 10670593, 618970019642690137449562111, 18861569, 23253381919, 162259276829213363391578010288127, 177722254122587407, 170141183460469231731687303715884105727

Offset: 1

Author

Roger L. Bagula, Nov 22 2008

Keywords

• nonn

Links

• Amiram Eldar, Table of n, a(n) for n = 1..34

Crossrefs

Cf. A046800, A152057.

Programs

Mathematica

Table[If[PrimeQ[s = Total[FactorInteger[2^n - 1][[;; , 1]]]], s, Nothing], {n, 1, 50}] (* Amiram Eldar, Jun 07 2025 *)

Extensions

Edited by N. J. A. Sloane, Nov 26 2008

Definition revised, offset corrected and more terms added by Amiram Eldar, Jun 07 2025